Drag force investigation in the collision between subaqueous mudflows and pipeline

Abstract

This paper describes an investigation of the events when sub-sea pipeline is impacted by submarine slide. Investigations are carried out by developing the model in the laboratory in the form of a collision between sub-aqueous mudflow with a pipe stem. Gravity flow concepts of fluid mechanics principles and lock-exchange system are adopted to build the laboratory experiment. It is implemented into a set of equipment of rectangular channel to generate the simulation of mudflow in water ambient. A crosswise pipe stem positioned at certain run-out distance is collided by mud flow. Mud model used is slurry of kaolin clay-water mixtures. The collision attributes of the collision event is including velocity, Reynolds number, maximum drag force exerted by mudflow, and drag force coefficient. All are observed based on percentage of kaolin clay content. The series of experiments is representing the estimation of drag forces exerted by muddy submarine slide on pipeline in the prototype condition.

Effect of pipeline surface roughness on peak impact forces caused by hydrodynamic submarine mudflow

“…As a highly destructive and sporadic load, submarine landslides, debris flows and mudflows, which are characterized by hydrodynamics, have caused great damage to submarine pipelines [1][2][3][4]; hence, these have become a research focus in recent years [5][6][7][8][9][10][11]. In terms of physical simulation, based on 1g single-phase (anhydrous environment) particle flow experiments [12][13][14], 1g flume experiment [15][16], rotating flume experiment [17] and Ng centrifugal model experiments [18], the researches on the interaction between submarine landslides and pipeline were carried out, the related laws were deeply explored, and reliable methods for assessing impact forces under simple working conditions were established. However, due to the shortcomings of physical simulation, such as substantial manpower and material input, limited conditions and insufficient acquisition parameters, numerical simulation has become the main approach for current researches.…”

Pipeline two-dimensional impact location determination using time of arrival with instant phase (TOAIP) with piezoceramic transducer array

“…Many pipelines are laid above the ground, and for these pipelines, accidents such as landslide and rockfall are increasingly impacting the safe operation of the pipelines [4][5][6][7][8]. Upon an impact, the pipeline may be damaged, and the damage may cause a pipeline leakage, which may result in severe consequences [9][10][11][12][13]. A method to accurately detect and locate the pipeline impact at a rapid pace is a pressing research topic.…”